The invention relates to network-device registration systems that allow devices on a local network, such as a cable network, to register with Internet service providers to obtain access to the Internet.
Cable modems handle incoming and outgoing data signals between a cable provider and a personal or business computer or television set. Cable modems are quickly replacing telephone modems in many areas because of the cable modem""s superior bandwidth.
DOCSIS (Data Over Cable Systems Interface Specifications) is an industry standard that specifies an interface for cable modems. More specifically, DOCSIS specifies modulation schemes and protocols for exchanging bi-directional signals between devices on a cable network and devices on a TCP/IP network, typically the Internet.
DOCSIS describes a method by which a cable modem can receive an IP address to gain connectivity to the Internet. This method is sufficient for the simple case where the cable provider supplies cable modems to cable customers, who then access the Internet through an Internet Service Provider (ISP) specified by the cable provider. However, there is no provision for cable customers to receive IP addresses for cable modems that are not supplied by their cable provider. Moreover, there is no provision for allowing cable customers to select from among several ISPs on a single cable network. There is therefore a need for a system that allows cable customers to choose both the cable modem through which they access the Internet and the ISP that will provide them that access.
The present invention is directed to methods and apparatus that let cable customers who wish to add a cable modem (or other device) to a local cable network choose both the cable modem through which they access the Internet and the ISP that will provide them that access.
A system of hardware configured in accordance with one embodiment of the invention connects the local network to the Internet. This hardware includes cable-modem infrastructure (CMI) that denies Internet access to devices on the local network that are not registered with an ISP authorized by the cable company. The hardware also facilitates the registration process, allowing devices new to the local network to establish Internet-access agreements with ISPs, and thereby gain access to the Internet.
Every network device, including cable modems, has a unique identification code called a media-access control (MAC) address. New devices connected to the local network send their MAC address out onto the local network in an effort to obtain a routable IP address (i.e., an IP address that can be used to gain access to the Internet). The CMI intercepts such requests and looks in a MAC database to determine whether the device associated with the MAC address is registered with an ISP, and is therefore entitled to a routable IP address. If the MAC address is not listed, the CMI assigns the modem a non-routable address that can be used on the local network, but cannot be used to gain access to the Internet. The unregistered device can then use the non-routable address to communicate with a registration server in the CMI. The registration server is adapted to facilitate communication between the device and a selected ISP.
Using the non-routable IP address and the registration server, a user of the network device enters into an agreement with a selected ISP. The selected ISP sends a message to the CMI identifying the device, the ISP, and the existence of the service agreement. The CMI then modifies the MAC database to indicate that the device is now registered. The CMI responds to subsequent address requests from the now-registered device with a routable IP address.